Methyl mercury ototoxicity: A model for the surface preparation technique

Abstract

AbstractA critical review of recent articles in which the surface preparation technique was employed is presented. Many of the reports were deficient in terms of five important criteria which would insure reproducibility of experiments, comparability of results from different investigators, and detection of a low level of cellular pathology. These criteria are: inclusion of concurrent controls; use of adequate number of control and treated animals to insure the detection of meaningful treatment‐control differences; adequate examination of controls; quantitative expression of cellular pathology, and the use of statistical analyses to test for significant differences.When these criteria were employed, methyl mercury was identified as a unique ototoxic agent. It caused a low level of outer hair cell pathology in all four turns of the guinea pig cochlea. Statistically significant damage occurred in the outer row of outer hair cells at 2½ turns from the cochlear base (P <.01) and in the inner row at 3½ turns (P <.05). When damage for all rows at each turn was considered, methyl mercury produced significant damage (P <.05) at 2½ turns from the cochlear base.